This airline will weigh passengers with their luggage before boarding flights; here's why

Starting next month, a top international airline will be rolling out a new instruction for its passengers: Step on a weighing scale. No, it's not just the luggage — those hopping on board the plane will be asked to get on the scales, too.

Air New Zealand will be conducting this exercise for five weeks until July 2, according to reports.

In its official advisory, the national airline says the weigh-in is part of a survey it is conducting to measure the "average weight of their passengers, including cabin baggage, on international flights".

This is being done "for safety reasons", Air New Zealand said. "For passengers, crew and carry-on bags, we use average weights that we get every five years through this survey."

Acknowledging how "daunting" it could be to step on scales and how weight is usually considered a private matter, the airline promises confidentiality.

"The scales do not display the weight as this is fed directly into a computer and recorded anonymously along with thousands of other passengers," it said.